When a massive Soviet battleship negotiates the treacherous Oslo harbor without a local pilot, American counterespionage agent David Harding suspects that the enemy has developed a secret navigational tool and orders his operatives to find a local frogman to take pictures of the vessel's hull when the ship makes a goodwill tour stop in England.
Key credits listed on this page include Ralph Murphy, Phyllis Stanley, John Mylong, and Robert McQueeney.